Unlimited-capacity direct-return trap.



I. P. CUNNINGHAM. UNLIMITED CAPACITY DIRECT RETURN TRAP.

. APPLICATION FILED APR. 22,191.4- l 1%,95. Patented Aug. 3, 1915.

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J. P. CUNNiNGHAM.

UNLIMITED CAPACITY DIRECT RETURN TRAP. APPLICATION mu) APR.22. 1914.

1,14;8,959. Patented Aug. 3, 1915.

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JAMES P. CUNNINGHAM, OF LITTLE ROCK, ARKANSAS.

UNLIMITED-CAPACITY DIRECT-RETURN TRAP.

Specification of Letters Patent.

Patentedi-hug. 3, rain,

Application filed April 22, 1914. Serial N0. 833,646.

To all whom it may concern:

Be it known that I, JAMES P. CUNNING- HAM, a citizen of the United States, residing at Little Rock, county of Pulaski, and State of Arkansas, have invented certain new and useful Improvements in Unlimited-Capacity Direct-Return Traps, of which the following is a full, clear, and exact specification.

This invention relates to steam heating systems and especially to means for returning the water of condensation to the boiler.

One object of the invention is to provide apparatus for this purpose which is automatic in its operation.

Another object is to provide such an ap paratus including an automatically operated trap and a receiver communicating therewith, the trap having an unlimited capacity determined by the capacity of the receiver and outlet which of course may be made any desired size to suit any particular plant.

Other objects will, appear as the description proceeds.

The invention will be first hereinafter described in connection with the accompanying drawings, which constitute a part of this specification, and then more specifically defined in the claims at the end of the description.

In the accompanying drawings, wherein similar reference characters are used to designate corresponding parts throughout the several views: Figure l is a front elevation of a steam heating plant equipped with my apparatus, for returning the water of condensation, and Fig. 2 is an enlarged detailed vertical section of the trap,.the normal position of the parts when the receiver is filling being shown in solid lines and the position of said parts when the receiver has become full and the water is running back into the boiler being shown in dotted lines.

In Fig. 1, A and A indicate two boilers of a steam heating plant, and a and a their steam domes which are connected by pipes c and c to the main steam header C. My improved apparatus includes a trap D and receiver E connected together as at e. A plurality of return pipes from the radiating units (not shown) are indicated at F entering the top of thereceiver. These return pipes are provided with check valves 7 which prevent the water. from passing back through the pipes when it has once passed said valves and entered the receiver and receiver pressure is equalized with that of boiler. One or more return pipes G and G to the boilers A and A lead from either the bottom of the receiver or the bottom of the trap. One return pipe must always lead from trap to boiler. It is to be understood, of course, that as many return pipes as are desired, whether one or more, may lead from the receiver to the boiler or boilers, one such return pipe being shown in the drawings, but theapplication is not intended to be limited to such a construction. As shown, one of said pipes leads from the receiver and the other from the trap. Said pipes are provided with check valves 9 and g for preventing the pressure in the boilers from forcing water therefrom up through said pipes into the trap and receiver when receiver pressure is lower than that of boiler. The pipe G, leading directly from the receiver to the boiler, serves to empty said re ceiver more quickly than would be possible if all the water in the receiver had to flow through the trap on its way back to the boiler. The main steam header C is tapped by a pipe 0 which leads to the upper end of the trap, and from the side of the upper portion of said trap, a vent pipe (Z extends. The trap may be also provided with a gage tube a? to show the height of the water in the same.

Referring now to Fig. 2, H and H designate two parts of a float device connected to gether by a link Z and housed in the trap D. The part or member H, which is arranged above, may be a standard float, but the part or member H is equal in weight to its volume in water. The float member H is located near the upper end of the trap D and ex tends above the receiver E so that it will not be operated until said receiver is nearly or quite full.

At the upper end of the trap there is a valve chamber J having a steam inlet K communicating with the pipe 0 Said chamber J also has an outlet K communicating with the vent pipe cl.

Within the chamber J, which is cylindrical in form, there is fitted to reciprocate a piston valve L having a stem Z and a small head or disk L 'at the end'ot'said stem. This disk L is fitted toreciprocate in a reduced extension J of the chamber J, which extension is also cylindrical and arranged concentrically with said chamber just within the outlet K, so that said disk cuts off direct communication of the chamber with the outlet at all times.

A passage M is formed'in the casing of the valve chamber, and opens at one end on in the plane of the inlet K and at its outer end m on the end of said chamber opposite from the outlet K. Said passage has an enlarged vertical portion m extending bcyond the end an, and in this enlarged portion or extension m there is fitted to reciprocate vertically a small piston valve N on a rod 0 extendin from the interior of the trap through the valve casing and out the top thereof, its outer end portion passing through a stuffing box P to prevent leakage of steam as will presently appear. At its inner end, the rod O is pivoted to a lever It at an intermediate point. One end of this lever is pivoted to a bracket 1 on the interior of the trap, while the other end of said lever is pivotally connected to the top of the float member H, so that when said fioat rises, the rod and small piston valve will be raised, and vice versa. The valve casing is further provided with a vent passage or by-pass S leading from the extension m of the passage M to the extension J of the valve chamber J beyond the outermost position of the disk L. A passage T is also formed in the casing, leading from said extension J at a point intermediate of the two positions of the disk L, to the interior of the trap.

When the trap and receiver are entirely or partly empty, the float device will be in its normal lowered position, as indicated in solid lines in Fig. 2. It will be noted that when the float device is in this position, the small piston valve N closes the passage M, so that the live steam in the chamber J acts upon the inner or left hand face of the valve L, holding this valve in the position shown in solid line, with the disk L cutting off communication between said chamber J and the passage T leading to the trap. \Vhen the valve is in this position, the live steam in the chamber J is also prevented from escaping through the by-pass S.

"When the trap and receiver become nearly or entirely full of water of condensation flowing back from the radiating units through the pipes F, the float member H rises under the influence of the rising water until it occupies the position indicated by the dotted lines in Fig. 2. This upward movement of the float raises the lever B, rod 0 and valve N until said valve occupies the position indicated in dotted lines, leaving the passage M open so that the live steam from the chamber J can act upon the outer or right hand face of the piston valve L to move said valve from dotted line position illustrated. This move ment of the valve shifts the disk L to the other side of the passage T so that live steam the solid line to the' may enter the trap through said passage and raise the pressure in the trap and receiver to a point equal the boiler pressure. As soon as this point is reached, the water in the trap and receiver will flew back into the boilers past'the check valves 9 and g in the return pipes G and G. When the receiver becomes empty, the float member H will pull the other float member down into normal position, thus shifting the valve N back to its normal position where it closes the passage M and cuts off the flow of live steam to the outer or right hand face of the valve L. The live steam then acting on the inner or left hand face of the valve L will move the same back to its normal position, thereby shifting the disk L so as to cut off the supply of live steam to the trap. As the valve L moves back to the normal position, the steam behind the same escapes to the outlet K via the bypass S, and the steam in the trap via passage T. By adjusting the pressure of the packing P around the pin'O, the floats H and H may be readily caused to operate as above described.

The trap being made separate from the receiver, may have various sizes of receivers connected thereto, making the apparatus practically of unlimited capacity. It will also be observed that inasmuch as the rod 0 projects beyond the valve casing, the small piston valve N, carried by said rod, may be operated from the outside in caseit should stick, which is a distinct advantage over prior constructions,it being diflicult to get into the trap to remedy this trouble.

It will be noted that when the passage M is open permitting the steam to act on the outer or right hand face of the valve L as well as on the inner or left hand face thereof, the pressure of steam on the inner face of the disk L will throw the balance of power onto the right hand side and result in the movement of the valve to the left as described. On the other hand, when the passage M is closed, the inner surface of the valve L is sufliciently larger than the inner surface of the disk L to insure said valve moving to the right back again into normal position.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is.

1. In apparatus of the character described, the combination with a trap, of means for delivering water of condensation to said trap, means for normally preventing flow from said trap, and means for automatically actuating said latter means to permit the water to flow from the trap when it reaches a predetermined level therein, including a float, a valve fitted to reciprocate in a chamber adjacent the trap, a smaller valve attached to the first valve but spaced therefrom and fitted to move in a small eX- tension of said chamber, there being a steam.

inlet passage opening in said valve chamber, an outlet passage from said chamber, and a passage from said chamber to the interior of the trap, means carried by the iirst mentioned valve for cutting ofl said passage to the trap from the valve chamber when the valve is in normal position, said chamber also having a passage leading behind the first mentioned valve, and a small valve connected to the float and normally closing said last named passage but adapted to open said passage when the float is raised, thereby permitting the steam to act upon the back of the first mentioned valve and move the same to open communication between the valve chamber and the interior of the trap.

2. In apparatus of the character described, the combination with a trap, of means for delivering water of condensation to said trap, means for normally preventing flow from said trap, and means for automatically actuating said latter means to permit the water to flow from the trap when it reaches a predetermined level therein, including a float, a valve fitted to reciprocate in a chamber adjacent the trap, there being a steam inlet passage to said valve chamber, an outlet passage therefrom, and a passage from said chamber to the interior of the trap, means carried by the valve for cutting off said passage to the trap, from the valve chamber when the valve is in normal position, said chamber also having a passageleading behind the valve and provided with an extension, :1- by-pass leading from said extension to the outlet passage, and a small. valve connected to the float and adapted to reciprocate in said extension, said small valve normally closing said last named passage but adapted to open said passage when the float is raised, thereby allowing the steam to act upon the back of the first mentioned valve and move the same to open communication between the valve chamber and the interior of the trap, said by-pass serving to permit the steam to escape from behind the first mentioned valve when the same is moved back to normal position.

3. In apparatus of the character described, the combination with a reservoir for water of condensation, of a trap communicating with the bottom of said reservoir, a pipe leading from said trap to the boiler ot a steam heating plant, and a direct return pipe from the reservoir to the boiler, the last named pipe being substantially the same size as the pipe from the trap to the boiler whereby said reservoir may be simultaneously drained through the trap and through said direct return pipe, check valves in said pipes to prevent flow from the boiler to the trap and reservoir, means for supplying steam from the boiler to the trap, a valve normally cutting oil such supply of steam from the trap, a float in said trap connected to said valve adapted to automatically open said valve when the water in the trap reaches a predetermined level, whereby the pressure in said trap will be raised to a point equal to the boiler pressure, causing the check valve to open and allow the water to flow from the trap to the boiler, and a weight for pulling down the float and 010s ing the steam inlet valve to the trap when a predetermined quantity of water has flowed from the trap to the boiler.

In testimony whereof I have signed my name to this specification in the presence of two attesting witnesses.

JAMES P. CUNNINGHAM.

Witnesses:

T. S. SHANNON, F. V. NmMEYnR.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, 1). G. 

